Drum stop means for printing machines



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2%; @bmwu J W. R. ALLEN Er AL DRUM STOP MEANS FOR IRINTING MACHINES Filed June 29, 1942 June 10, 1947.

June 10, 1947. w. R. Al LE N ET AL 2,421,323 bRUM STOP MEANSFOR PRINTING MACHINES 1 Filed June 29, "1942 a Sheets-Sheet 2 Jar ators. fiujllen and fi'karles JY. Jand Jttornm June 10, 1947. w, R, ALLEN r AL 2,421,823

DRUM STOP HEANS FOR PRINTING MACHINES Filed June 29, 1942 a Sheets-Sheet s Jr'u/niaro: Ida/hum 1?.Jllerz and Charles H. Jand vldfarnm.

June 10. 1947. w. R. ALLEN EI'AL DRUM STQP MEANS FOR PRINTING MACHINES FiledJune 29, 1942 a Sheets-Sheet 4 Jllorm a June 10, 1947.

W. R. ALLEN ET AL DRUM STOP MEANS FOR PRINTING MACHINES Filed June 29, 1942 8 Sheets-Sheet 5 .[n/enfora:

l1/illiam RAJ/[en aid 6karlea 15 Jane! June 10, 1947. w. R. ALLEN ET AL DRUM STOP MEANS FOR PRINTING MACHINES Filed June 29, 1942 8 Sheets-Sheet 6 lfie/ntora. William 1?..{1180 and fiarles E Jand liter/up June 10, 1947. w. R. ALLEN arm. 2,421,823

DRUM STOP MEANS FOR PRINTING MACHINES Fi1ed- June 29, 1942 a sheets-sheet '1 M'Zlz'am Rfllllen am Z Charla; fi'. Jana! .ZFnnfora June 10, 1947. w. R. ALLEN ETAL 2 DRUM STOP MEANS FOR PRINTING MACHINES Filed June 29, 1942 8 Sheets-Sheet 8 1527/5725070'; (William JRfi/len arza. harles H Jana! I] a.w Jf/arrzeys Patented 10, a 1947 DRUM STOP MEANS FOR PRINTING MACHINES William R. Allen, Shaker Heights, and Charles H.

Sand, Willonghby, Ohio, assignors to Addressograph-Multigraph Corporation, Wilmington, Del., a corporation of Delaware Application June 29, 1942, Serial No. 448,912

4 Claims. (01. 101-442) This invention relates to printing machines and particularly to those which embody a rotary printing couple and especially to those in which an image carried by a lithographic master is transferred to a blanket and is thereafter transferred onto sheets or the like.

The master that is included in printing machines of the aforesaid character is customarily of the time lost in manually manipulating the removably retained in operative position in the machine so that it may be replaced from time to time. In many uses to which printing machines of this character are put the master is retained in the machine for relatively protracted periods inasmuch as in such circumstances a large number of sheets or the like receive impressions from the same master. However, there arelmany, instances wher but a relatively small number of sheets are to receive impressions from a particular master, as in the instance of the preparation of an insurance policy where certain data are printed on the policy and also on file cards and other records that are retained by the company issuing the policy, and in such circumstances ofttimes no more than ten, or even fewer impressions are made from each master installed in the machine.

Particularly in circumstances where but a relatively few sheets are to receive impressions from a particular master that is removably mounted in a printing machine it is advantageous to enable the master to be expeditiously installed, and one 01' the important objects of this invention is to enable this to be effected in a novel manner.

Inasmuch as it is an inherent characteristic of printing machines of the character to which this invention pertains to have the printing couple so arranged that the elements thereof may be freely rotated, it has been customary heretofore, when one master was to be replaced by another, to bring the machine to rest and to thereafter manually manipulate the drum or cylinder on which the master was to be retained so as to bring the drum into such position that the operator of the machine could have access to the means which are eflfective to secure the master on the drum or cylinder and, while this is not particularly objectionable in those instances where the master need be changed but infrequently, as where a large number of sheets receive impressions from the same master, in those instances where the master is to be replaced relatively frequently, it has been observed that the requirement that the drum be manually manipulated, as aforesaid, has interfered with drum so as to enable the substitution of one master for another. Hence,.yet'another object of this invention is to enable the drum or cylinder on which a master is to be mounted in a printing machine to be brought to re t in such position "as will expedite substitution of one master for another or other installation of a master in the machine.-

In many printingmachines of the aforesaid character, it is necessary that the masterbe maintained taut on the drum or-cylinder on which it is mounted and in order that this may be effected it is customary in many instances to fixedly retain one end of the master and to so arrange the other end of the master that resilient means will be effective thereon to thereby retain the master-in taut condition on th periphery of the drum or cylinder, In arrangements of this character there" are usually two places whereat the ends of the master may be connected to the drum or cylinder and, with respect to such arrangements, it is yet another object of this invention to enable a drum or cylinder of the aforesaid character to be brought to rest in such position as will facilitate the: attachment of each end of a master thereto, and a related object is to enable a drum of the aforesaid character to be brought to rest in such position as will expedite the attachment of one end of a master thereto and to thereafter enable the drum to be so manipulated that it will be brought into such position that the other end of the master may be expeditiously attached thereto.

In printing machines of the aforesaid character the rotary parts of the printing arrangement are usually so arranged that they may be expeditiously connected to or disconnected from the customary power-operated driving means therefor and to this end it is customary to interpose a clutcharrangement intermediate such driving means and the rotary elements of the printing couple, and such a clutch is usually arranged so as to enable manual control thereof. Therefore,

still further objects of this invention are to so control the operation of a clutch arrangement of the aforesaid character that the rotary elements of the printing couple, and particularly the element or cylinder on which a master sheet is to be attached, that particularly such element may be brought to rest in selected positions under control of the clutch; to so arrange the control of the clutch of the aforesaid character that the printing elements of theprinting machine may efiicient use of the machines, particularly in view be optionally kept in continuous operation ortbe caused to operate in a step-by-step manner so as to thereby bring those portions of the drum or cylinder, to which the ends of a master are to be attached, into positions which will facilitate attachment to, or detachment therefrom, of a master; and to so control a clutch arrangement f the aforesaid character that a drum to which a master is to be attached may be first brought to rest in one selected position and thereafter be brought to. rest in another selected position so as to enable the respective ends of a master to be connected to or detached from the means which are to be respectively effective toconnect such .ends of the master to the drum or cylinder. I

Other and yet more specific objects 01' the invention are to utilize a friction clutch which will be effective to control operation of particularly the drum or cylinder on which a master sheet is to be'attached in the manner described hereinabove; to enable separable elements in-a friction clutch arrangement of the aforesaid character to be automatically disengaged at selected times and thereby so regulate the positions at which such drum or cylinder comes to rest as to enable a master to be attached thereto or detached therefrom in the manner'described hereinabove; to brake the released portions upon disengagement of the clutch in the'manner just described and thereby insure prompt arresting of the movement of such released parts; and yet other and related objects are to employ a clutch arrangement which will positively stop a drum of the aforesaid char--. acter in selected positions; and to so arrange either of such clutch arrangements that means which are operative to effect disengagement thereof may be rendered ineffective so as to th'ereby enable the drum and other printing elements of the printing machine to be operated continuously when and as desired.

In many instances in the use of printing machines of the character to which this invention pertains it is necessary to moisten or otherwise treat the master sheet. For example, in those instances where a lithographic master is utilized it is necessary that the non-image bearing areas thereof be resistant to ink so that only the image will be picked up by the blanket or transfer medium when ink is applied to the master and the image. thereon is thereafter brought into operative relation with the blanket. While in many instances the master may be so treated prior tothe time it is installed inthe machine and while in other instances a treatment of the aforesaid character is continuously applied to the master in the course of use thereof, there are instances where it is advantageous to treat the master in the aforesaid manner after it is installed in the machine and then but once or at least only intermittently. One particular instance where it is even fewer impressions are to be made from each. master. In such circumstances it may be disadvantageous to treat the master before it is installed in the machine for in the subsequent handling of the master, as during installation thereof in the machine, the hands of the operator may become soiled and time will be lost while the operator's hands are being cleaned or, in the alternative, if the operator feeds sheets to the machine, soiling of the sheets and the like may result.

when the master is initially installed in the machine or from time. to time in the course of use of the master should this be found to be necessary; to so arrange an apparatus of this character that a quantity of the material required in the treatment of the master may be stored therein; to utilize the wick arrangement for withdrawing the material required in the treatment from the quantity thereof stored in the apparatus and v for applying 'the material to the master; and to facilitate installation and operation of an apparatus of the aforesaid character.

In those offset printing machines which embody a cylinder adapted to have a lithographicor like master mounted on the periphery thereof and wherein another cylinder is provided which is adapted to have a blanket or other transfer medium mounted on the periphery thereof, the arrangement is such that the image borne by the master mounted on the periphery of the first drum is transferred tothe blanket which is thereforev efiective to transfer the image so picked up to sheets or the like. In such an arrangement it may sometimes be desirable to enable less than all of the image borne by the master to be transferred by the blanket or the transfer medium to the sheets and while, particularly in instances where a large number of sheets are to receive impressions, this may be effected by 'masking the portion of the image which is not to be produced, as by adhesively applying a. thin sheet over the. portion of the image borne by th master which is not to be produced, this entails interruptingv the operation of the machine and is otherwise not entirely satisfactory.

Furthermore, in other instances, the portion of the image which it is not desired to reproduce may be so related to the'portions which it is desired to reproduce that such portions will be arranged in spaced apart relation axially along the extent of which the cylinder on the master is mounted. In such, instances a gauge or the like may be provided to so determine the point whereat the sheets are to pass into the bite between the platen roller is normally spaced from the surface assigns 1:

of the image which it is desired to transfer and.

particularly in instances where but arelativeiy small number of sheets are to receive impressions in such circumstances, it is advantageous to so arrange the machine that selected portions of'an image borne by a master will not be transferred to the sheets or will be cut of! as it is known in the art, and to enable this to be effected in a novel and efficient manner is yet another object of our invention. Y i Other and further objects related to this last set forth object are to enable such relative movement to be eifected between a master and the. cylinder on which it is mounted in the arrange- 3.116, l l t illustrated in 12in another ofthe operative positions thereof? Fig. is a vertical sectional detail view taken substantially on the line I 5-" on Fig. 13; g

Fig. 1615 a fragmentary vertical sectional view similar to Fig. 12 but showing another form of our invention;

Fig. 17 is a fragmentary front elevational view of a portion of the blanket drum illustrated in .10-

Fig. 16; and

Fig-18 is a fragmentary detail view showing certain of the parts illustrated in Fig. 17 in another of the operative positions, thereof.,

The form of our invention illustrated in'xFigs. 1 to 8, inclusive, is included in a printing machine which, in the present instance, is of the onset lithographic type and which embodies a frame or stand 15 that includes two vertically disposed inder on which the master is mounted or the cylinder on which the transfer medium is mounted, or both of these cylinders; so as to thereby enable a cutoif of the aforesaid character to be effected; to enable the foregoing to be accomplished in certain instances, without interrupting the master. the blanket or either of these elements and in other instances to afford an arrangement such that a portion of the master or the blanket or portions of both may be connected to a retractable part so as to thereby enable one or morecutofls to be effected. v

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show preferred embodiments and the principle thereof and what we now consider to be the best mode in which we have contemplated applying that principle. Other embodiments of th invention embodying the same or equivalent principle may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings,

Fig. l is a side elevational view of a printing machine embodying our invention;

Fig.2 is a front elevational view of the machine shown in Fig. l;

Figs. 3, 4 and 5 are sectional views taken substantially and respectively on the lines 3-3, 4-4

and 5-5 on Fig. 2;

Fig. 6 isa sectional detail view taken substantially on the line t---@ on Fig. 5;

Fig. 7 is .8, view similar to Fig. 6 but showing certain of th parts in another of the operative positions thereof;

Fig. 8 is a sectional detail view taken substantiully on the line 8-8 on Fig. 7;

Fig. 9 is a fragmentary side elevational view somewhat similar to Fig. l but showing another form of our invention;

Fig. 10 is .a, fragmentary front elevational view of the apparatus illustrated in Fig. 9;

Fig. 11 is .a vertical sectional detail view taken substantially on the line l|-|| on Fig. 9;

' Fig. 12 is a. fragmentary vertical sectional view illustrating a. further aspect of our invention;

Fig. 13 is a front elevational view of the apparatus as illustrated in Fig. 12;

Fig. 14 is a fragmentary verticarsectionai detail-view showing certain of the operative parts side plates l6 and I1 between which various operative parts of the machine are disposed. Thus,

a cylinder C is mounted on a shaft I9 .Iournaled in the side plates I8 and I1. A blanketlll is removably mounted on the periphery of the cylinder C and cooperates with a platen roller 2|,

Fig. 3, to produce oflset impressions on sheets or the like which are passed into the bite of the cylinder C and platen roller II. The image which is to be thus printed upon the sheets is transferred thereto :by the blanket 20 from. a, lithographic master sheet M removably mounted on the periphery of a cylinder or drum 2: carried by a. shaft 23 jourmaled in the side plates i6 and II. An inking roller 24 cooperates with the master sheet M to ink the image areas of the master sheet in the manner well understood in the art. Ink is supplied to the roller 24 by a conventional inking unit 25 which includes a ductor roller 26 that periodically conveys ink from, a fountain in the unit 25 to the inking roller 24. A distributing roller 21 cooperates with the inking roller 24 to evenly distribute the ink over the surface of the roller 24. A wiping roller 28 is alsodisposed to cooperate with the master sheet M on the drum 22 for a purpose to be explained presently, this roller 28 being-out of contact with the inking rollers 24 and 21.

The sheets which are to be printed are fed. one

at a time across a table lilLFigs. 1, 2 and 3, into the bite of the printing couple comprising the. platen roller 2| and blanket cylinder C. As each sheet passes through the printing couple it receives an impression of the image from the blanket 2|! and is then discharged to a receiving rack or collector 3|. The platen roller 2| is mounted on a shaft 32 journaled in a rocker including arms 33 which are pivotally mounted on a rod 34 extending between the side plates l6 and ii. The arms 33 are interconnected by a cross bar35 which is received in the slotted heads of screws 36 that extend downwardly through openings in a stationary cross bar 31 secured to the side plates 96 and il. Coil springs38, encircling the screws 36 intermedlatethe slotted heads of these screws and the cross bar '31 tend to urge the rocker carrying the platen roller 2| upwardly,

but such action of the springs 38 is limited by arrangement is such that the platen roller will not pick up ink from the blanket in an instance where a sheet is not disposed between the roller 2| mild the blanket on the periphery of the'cylinder 8,

The periphery of the blanket cylinder I2 is interrupted, as shown in Fig. 3, and the blanket 20 is stretched over the periphery of the cylinder between the edges along the recess aflording the interruption. The ends of the blanket 20 are scalloped, as shown in Figs. 2 and 4, and slots are formed in these scalloped end portions to enable the blanket to be anchored to hooked projections 4| on rockers 42, Figs. 2 to 4, which are disposed in the recess in the cylinder Hi. The rockers 42 are pivotally mounted on rods 43 extending axially of the cylinder l8 and fastened to the solid end portions of this cylinder. Screws 44 are threaded into the rockers 42 and bear against the edges of the recess in the cylinder and by adjusting these screws, the blanket 20 may be drawn taut over the impression surface of the cylinder IS.

The drum 22 on which the master sheet M is removably retained is of the same diameter as the blanket cy1inder'l8 and likewise has an interrupted cylindrical impression surface. A recess 4'! is formed in the cylinder 20 to receive a bar 48 having hooked projections 49 for anchoring one end of the master sheet M to the drum 22, the bar 48 being secured to the drum 22 in any suitable manner. The other end of the master sheet M extends slightly beyond an end of the cylindrical shell of the drum 22 and is anchored to a rocker 50 disposed in the recess in the drum 22. The rocker 50 is pivotally mounted on a rod extending axially between the end portions of the drum 22 and is provided with hooked projections 52 which are received in holes in the end of the master sheet M. The portion of the surface of the drum 22 on which the projections 52 are mounted is slightly relieved so that it cannot contact the blanket 20. Springs 53 are extended between a rod 54 on the rocker 50 and a rod 55 secured in the drum 22, these springs serving to place the master sheet M under tension to maintain it taut and smooth on the drum 22.

A clamping plate 55, Figs. 2 and 3, is pivotally mounted as at 550m the rocker 50 and is urged by a spring 5'l against the outer end of the rocker 50 to firmly clamp the end of the master sheet M thereon. The freeend of the clamping plate 55 is provided with aknob 58 to facilitate manipulation of the clamping plate when it is desired to insert or remove a master sheet. Tongues 59 struck out from the clamping plate 55 are disposed to engage the spring anchor rod 55 on the rocker 50 when the clamping plate 55 is pivoted against the action of the springs 5?. This is done when it is desired to release the end of the master sheet M or insert a new master sheet, the tongues 59 bearing against the rod 54 and swinging the rocker 50 against the action of the springs 53 as the knob 58 is pushed inwardly. Stop pins 60 secured to the ends of the drum 22 limit the movement of the rocker 55 under the influence of the springs 53 when no master sheet is on the drum 22. Hereinafter the end of the master sheet M anchored to the fixed bar 48 will be referred to as the leading end thereof, and the end which is anchored to the spring-urged rocker 50 will be designated the trailing end of the sheet.

The inking roller 24 is mounted on a shaft 65 journaled in bearing blocks 65, Figs. 1 and 3, which are arranged to slide in slots 61 in the side plates 16 and H. Springs 68 are extended between the ends of the shaft 65 and pegs 69, Figs. 1 and 2, fastened to the outer faces of the side plates lt and ll. The wiping roller 28 i mounted on a shaft l3 journaled in bearing blocks 14 slidll. Springs 18 are extended between the ends of the shaft I2 and the pegs 28 on the side plates l6 and II. The springs 68 and 16 tendtourge the inking roller 24 and wiping roller 28 radially to.- ward the drum 22 and the master sheet M carried thereby. The bearing blocks 55 and 14 in which the shafts 65 and 13 of the rollers 24 and 28 are journaled are adapted to cooperate with sloping shoulders on cam plates 18, Figs. 1 and 2, which are slidably mounted on the outer faces of the side plates I6 and Ill. The ink distributing roller 21 is mounted on a shaft 10, Figs. 1, 2 and 3, journaled in the cam plates 18. Screws '19 passed through vertical slots in the cam plates 18 are threaded into the side plates 16 and I! to guide the cam plates 18 for vertical movement. A shaft 80, Figs. 1 and 3, passing through the side plates 16 and I! and openings in the cam plates I8, carries eccentrics 8| which cooperate with rollers 82 mounted on the cam plates 18.

The shaft is provided with a handle 83, Figs. 1 and 2, by means of which the shaft 80 may be turned to bring the high portions of the eccentrics 80 into cooperation with the rollers 82, thereby elevating the cam plates 18. As the cam plates 18 are thus raised, the sloping shoulders thereon cam the bearing blocks 66 and 14 radially out- In order to return the inking roller 24, spreading roller 21 and wiping roller 28 into cooperative relation with the master sheet M on the drum 22, the handle 83 is turned until the low portions of the eccentrics 8| cooperate with the rollers 82 on the cam plates 18, whereby the cam plates 18 are lowered to enable the springs 58 and 16 to restore the rollers 2 21 and 28 into the positions shown in Fig. 3. The shoulders of the cam plates are supported by adjustable stop screws in the bearing blocks 66 and M to prevent the inking roller 24 and wiping roller 28' from dropping onto the relieved portion of the drum 22 or into the recess of this drum but the arrangement is such as to enable the rollers 24 and 28 to contact the master sheet "M.

In placing a new master sheet on the drum 22, the leading edge of the sheet M is first attached to the anchor bar 48 on the drum 42, Fig. 3, and the trailin end of the master sheet is thereafter attached to the spring-urged rocker 50. This requires that the drum 22 shall first be disposed in a position in which the operator may conveniently have access to the bar 28 (the drum 22 being shown approximately one hundred eighty degrees away from this position in Fig. 3) and then the drum is so disposed that the trailing end of the master sheet may be fastened to the rocker 5B (in which position the drum is shownin Fig. 3). For the purpose of conveniently locating the drum 22 in these two desired positions we have provided a clutch mechanism, presently to be described, which enables this to be expeditiously effected.

As shown in Figs. 2 and 3, a gear 85 is mounted coaxially of and secured to the drum 22, and this gear meshes with a gear 86 similarly connected to the blanket cylinder l8. A gear 81 connected to the platen roller 2| meshes with the gear 86 and the arrangement is such that the platen roller 2| may be adjusted relative to the cylinder ably arranged in slots 15 and the side plates l8 and 75 iii, in the manner explained hereinabove. without clutch 96.

demeshing these gears. A shaft 90, Figs. 3 and 4, extending between and journaled in the side plates I6 and I! carries a pinion 9| which meshes with the gear 66'on the blanket cylinder I6. A gear 92 fixed to the shaft 90 outwardly of the side plate l6 meshes with a pinion 93 on a shaft 94, hereinafter referred to as the drive shaft, which is journaled in a bracket 95 secured to the outer face of the side plate I6. A disc clutch generallydesignated 96 is mounted on the drive shaft 94 adjacent the pinion 93, and the driving member of this clutch includes-a pulley 91 which is connected by a belt 98, Figs. 1 and 2, toapulley 99 on the shaft of a motor I supported by a stand I5, this motor furnishing the power for operating the machine.

In order to couple the driving pulley 91 to the drive shaft 94 it is necessary to apply axial pressure against the discs of the clutch 96. To this end, two lever arms I03 are pivotally, mounted on small plates I04 pinned to the shaft 94 on opposite sides thereof. The levers I03 extend axially of the shaft 94 and the corresponding ends thereof are arranged to bear against the outer disc of the A clutch operating member in the form of a collar I05 has a conical face that is adapted for cooperation with rounded portions at the free ends of the levers I03, the collar I05 being splined to the drive shaft 94. When the collar I05 is advanced toward the clutch 96 it engages and spreads the arms I03,'causing them to exert pressure on the discs of the clutch 96 and operatively engage the same to thereby couple the pulley 9'I tothe drive shaft 94.

A. shifting lever I06 is effective to move the collar I05 into and out of the position in which it is effective to engage the clutch; this lever being pivotally mounted on a bar I 0'I secured to the bracket 95. A roller I08, Fig. 4, mounted on one arm of the lever I06 is disposed in a circumferential groove in the collar I05 and a spring IIO,'

anchored to the bracket 95, acts on the'other arm of 'the lever I06 and tends to urge this lever in such a direction as to cause the collar I05 to. be

' disengaged from the lever arms I03. When the.

lever I06 is released to the action of the spring IIO the collar I05 is brought to bear against the' hub of a brake disc III which is slidably but nonrotatably mounted on the drive shaft 34. A friction element II 2 secured to the face of the disc I I 1o I downwardly and this in turn is effective through the vertical link H6 to move the arm I06 of the lever-I 06 downwardly whereupon the tapered portion of the collar I06 movesinto engagement with. the levers I03 to thereby engage the clutch 96.-

whereupon the cylinders and platen roller are set in rotation, and. rotation thereof continues so long as pressure is applied to the pedal I26.

In some instances, however, the drum 22 on V which the master sheet is mounted, isadvantageously operated in a step-by-step manner so as to thereby bring the portions thereof to which the ends of the master sheet are to be connected'into position to be disclosed toward the side of the machine from which the feed table projects, at which side of the table the operator normally stands so as to have access to the pedal I26.

Hence the bracket 95, Figs. 2 and 4, which supports the driving mechanism includes a depending portion I30, Figs. 5 to 8, on which a latch member I3I is pivotally mounted adjacent to the lever I06. A spring I32 tends to urge the latch member I3I against the lever I06 and, when the effect engagement of the clutch 96 as aforesaid, a shoulder I33, Figs. 5 and 8, on the latch I3I moves into position above the lever I06and reabove the arm I06".

However, as hasibeen explained'hereinabove, it is often desirable to bring the drum as 22! to rest in selected positions toenable the ends of the master sheet to be connected thereto and to this end a two-lobed cam I36, Figs. 2, 5 and 6, is pro- I vided in the present instance, and this cam is I in the path of movement I II cooperates with a flat surface on the outer end of the bracket 95 surrounding the shaft 94, and when the collar I05 is urged by the spring IIO against the hub of the disc III, the friction element H2 is effective to exert a braking force to arrest and hold the drive shaft 94 so long as it is uncoupled from the driving pulley 91..

The arm; I06 of the shifting lever I06 to which 7 r the spring H0 is fastened is connected by a vertical link H5 to an arm II6 on a rock shaft 1, Figs. 1, 2 and 3, journaled in brackets I I8 secured to and depending from the lowerends of the side plates I6 and I1. Anotherarm II9 on the rock shaft H1 is connected by a vertical link I20 to a lever I2I which extends into, and which is pivotally mounted in, a housing I22, Figs. '1 and 2,

depending from a cros bar I23 on the stand I5." The lever I2I is connected by a link I24 toa lever I25 pivotally mounted in the housing I 22 and having'a foot pedal I26 trudes from the housing I22 stand I5 below the feed table 30.

thereon which properation, the operator applies pressure to" the pedal I26 and thereupon the lever I2I is pivoted near the base of the When the machine is to be kept in continuousmounted on the shaft I9 on which the drum or cylinder C is mounted to be rotatable therewith and, since the drumsC and 22 rotate synchronously, this cam rotates in timed and fixed angular relation withthe drum 22'. An ear I36 is formed on the latch I3I and is disposedto lie I35. Each of these lobes is located in suchp osi-. tion that upon engagement 01' either suchilobe with the ear I36 the latch I3I is moved against the effect of the spring I 32 and out of latching relation with the arm I06. when this occurs the lever I06 is freed to the effect of the spring II 0;

and thereupon the collar I05 is retracted from cooperating relation with the levers I03 to thereby effect disengagement of the clutch 96, and. at this: same time the friction element 2 on the disc III engages the, fiat surface on the bracket and brakes rotation of the drive rest. or course, so longas pressure, is applied to the pedal I 26, the lobes of the camI36-are ineffective to' efiectsuch disengagement ofthe clutch96. -1 1 6 Hence, when the parts are in the position shown in Fig. "3,.the operator may momentarily apply pressure to the foot pedal l26-to bring about en-- gagement of the clutch and thereupon the drum 22 is set in operation. However, if the operator I does not continue toapply pressure on the foot,

engages theear I36 with the effects hereinabove described so that the drum comes to rest in of the lobes on thecam.

shaft 94 with the, result that the drum '22 is promptly brought to .11 such position that the anchor bar 40 Is accessible to the operator and then the leadingend of a master sheet M may be attached to, or detached from, the anchor bar;

At a time when the machine is to be operated in this manner the handle 83 is desirably manipulated to lift the inking roller 24, the distributing or spreading roller 21 and the wiping roller- 28 away from the periphery of the drum 22 inasmuch as such parts of the apparatus .are to be rendered inefl'ective when a master sheet is to be initially attached to the drum 22.

However, once the drum22 has been brought to rest in the manner above described and the operator has attached the leading end of a master sheet M to the hooks 49, the foot pedal'l26 is again manipulated to again engage the clutch' 96 and thereupon the drum 22 is set in-rotation, and this continues until shortly before the drum 22 attains the position thereof'shown in Fig. 3. If, at this time, pressure is not maintained on the pedal I26, the other lobe on the cam I35 acts on the ear I36 to again cause disengagement 12 side plates I6 and I1 and this member afiords a well in which the conditioning fluid may be stored. A wick I42 extends from the well in the trough-like member toward the periphery of the'druin 22 to be engageable therewith. However, since the wick I42 is to be intermittently engaged with the master sheet, an arm I43 is sethis spring tending to retract the moistening device'I40 so that the wick I42 normally does not engage the drum 22 or the master sheet M thereon. Retraction of the moistening device I40 by the spring I44 is limited by the engagement ofthe pin I48 with one end of the slot I41 in the link I 46. The link I46, Figs. '4 and 5, is pivotally to the side plate I6 projects and a finger piece I49 is formed on the free end of thislink to be disposed at the side ofthe machine from-which of the clutch 96 and braking of the shaft 94.

The operator then manipulates the knob 83 and the clamp plate 55, Figs. 2 and 3, to swingthe clamping plate 55 upwardly and thereby dispose the hooks 52 back of the openings to receive the same at the trailing endof the master sheet. Then when the rocker 50 is released,'the hooks 52 enter these openings as the clamping plate 55 moves inwardly and thereupon the trailing end of the master sheet is clamped in position, the springs 53 acting on'the rocker 50 to apply tension to the master sheet and thereby maintain it taut on the periphery of the drum 22.- The master sheet is then retained on the"drum and in position to ave impressions made therefrom.

In instances however, where the master'sheet M is lithogra hic in character, it-is first treated to render the nonimage bearing portions thereof ink-repellent, but once this has-been done'the handle 83 is again manipulated-so as to render ,the table 30 projects so thatthe operator may conveniently grasp the link and thereby rock the trough-like member about the rod I to bring the wick. I- 4 2'into.engagement with the master sheet M on the drum 22'whenever this is desired.

.When'the master sheet M has been attached the master sheet M passes the wick I42 the conditioning vfluid is applied thereto for the purpose explained. Once the master sheet M has been is released and the spring I44 then disengages the wick from the master sheet and thereafter the inking roller 24, the distributing or spreading roller 21 and the wipingroller 28 effective: Subsequently and so long as pressure is applied to the foot pedal I26 and-sheets are fed into the bite between the blanket 20 and the platen roller 1 2|, impressions may be made onto sheets fed into this bite from the feed table 30.

frequently desirable to treat a master sheetas M prior to the time impressions are to be made therefrom and in instances where the'master moistened or otherwise treated after it has been installed on the drum 22, we have provided a moistening device I40, Figs. 3 and 4, for applying a conditioning fluid to the master sheet as M when it is mounted on the drum 22 and this drum is set in rotation. The moistening device so It has been explained hereinabjove that it is the inking roller 24, the spreading roller 21 and the wiping roller 20 may be lowered into their effective positions, shown in Fig.3, by turning the handle. 83, 'Figs. 1 and-2, and the machine may ''becontinued in operation. The wiping roller 28 serves to absorb any excessive conditioning' fluid from the surface of the master sheet M prior to'movemen't of the master sheet into cooperation-with th'e inking roller 24. Then. as the master sheet M moves past the inking roller 24 it'picksi up ink on image areas thereof and then moves into cooperation with the blanket 20 .on-the cylinder I8, leaving an inked impression of. the image'on' this blanket. The platen roller 2I is spaced from the blanket 20 sufllciently so thatno 'ofl'set impressions will be made on a platen roller in the absence of a sheet intermediatethe cylinderv I8 and roller 2I. The sheets to be printed-are fed by hand over the feed table 30 into the bite between the blanket cylinder I2 and the platen cylinder 2|, although, of course,

it will be understood that an automatic feeding I .is located to the left, as viewed in Fig. 3,

In the present instance, the moistening device includes a trough-like member whichis suspended from'a rod I4I.' extending -betWeen the means may be employed.

' In the type of work for which the present in vention is adapted to be used, only a limited number of sheets .are'printedfrom each master sheet M and usually it is necessary to make only one application of the moistening fluid to each master sheet. In the event, however, a relatively large number of sheets or the like are each to receive an impression from a particular master, it may be necessary to apply the conditioning fluid to the master sheetfrom time to time in the course of such printing operations. This inclusive.

maybe conveniently doneby actuating the moistening device I", inthe manner above explained, Y

when and as required. It will be appreciated that the inclusion of a moistening device as I in a I machine of the character to which this invention pertains is, therefore. quite advantageous inasmuch as it materially'expedltes applying treatment to master sheets'that are mounted on the drum adapted to receive the same either whena master sheet is initially installed or from time to time in the courseof use thereof.

The wiping roller 28 is absorbent incharacter and the master sheet is passed into engagement therewith prior to the time it passes to the ink applying means and thus the wiping roller 28 may be and is eilectiveto remove any excess conditioning fluid that may be applied to the master upon manipulation of the moistening device I in the manner'hereinabove explained. If in the course of use of the machine thewiping l0 imparted to the lack. shaft I52 is transmittedthrough the pinionjl! and' 'the gear III to a shaft m, as mdicateastjmgftaisiack shaft being Journaledin a bearing III in the bracket 95 and a suitable bearing provided in the side plate Ila. Power is transmitted through a belt 98a from a motor-as I" to the pulley Ila and thence to the jack shaft I52 and hence so long as'the motor is lnpperatiojn the jlacki shaft "2 is rotated.

A pinion I on the jack shaft it: messes with a gear I58 fast on the shaft a andmovement pinion I51 also faston theshaft 99a. A gear roller 28 should become saturated, it maybe readily removed from the machine and run over" a sheet of. absorbent material such. as blotting paper or the like whereupon the moisture content therein will be reduced so as to thereby insure that the wiping roller 28 will be properly conditioned to perform its intended function;

As is usual in machines of the character to.

which this invention pertains, a hand wheel I50, Figs. 2 and 4, is mounted on the shaft 99 outwardly of the side plate I1 and this .enables the I58 rotatably mounted on the shaft IIameshes with the pinion I51, and therefore thagear Ill The clutch to which reference has just been made includes a housing I59 that embodies a hub that is pinned or otherwise suitably secured to the shaft Isa, as indicated at intend, as best shown in Fig. 9, an opening IQI is formed in the flanged periphery of the housing I59. The nose drum 22 and the parts movable therewith to be manually manipulated when and as required. as for'bxample in instances where the drum 22 does not stop in the precise position desired to facilitate attachment of an endv of a mastersheet thereto. I

In the form of the invention thus far described a friction clutch is employed to drive the rotatlng parts oi the printing mechanisms and a friction brake is relied upon to bring the drum as 22 to rest in selected positions as in those instances where the ends of a master sheet is to be attached thereto. In certain circumstances, however, it may be advantageous to bring the drum 22 to rest in positively determined positions, and an arrangement which will enable this to be accomplished is illustrated in Figs. 9 to 11,

Inasmuch as many of the parts illustrated in Figs. 9 to 11 correspond to those described hereinabove, except in so far as the particular clutch mechanism is concerned, those parts shown in' Figs. 9, 10 and 11 which correspond to the parts shown in Figs. 1 to 8, inclusive, are des-'- ignated by the same reference character but the sufflx a is added to these reference characters in Figsf9, l0 and 11. Moreover, while the shaft 90a shown in Figs. 9 and 10 is to have a hand wheel as I59, Fig. 2, secured thereto, the shaft 90a does not carry a pinion corresponding to the pinion 91, Fig. 2, for in this instance the shaft Ilia, which otherwise corresponds to the shaft I9, is arranged to be driven and a gear corresponding to the gear 86 is fast to the shaft We and meshes with a gear 85 associated with I a cylinder or drum as 22 so that when rotative movement is imparted to the shaft 19a, the drums C and 22 rotate in synchronism, as explained hereinabove. a

In the form of the invention shown in Figs. 9, 10 and 11 a bracket is'fast to the outer face of the side plate Ilia and includes a bearing I-5I in which an end of the shaft 90a is mounted.

A pulley 9141 has the hub thereof pinned to a jack gear I58 on the shaft I9a.

I62 of a clutch dog I83, which is pivotall mounted asindicated at I64 on the housing IE9, is

urged through the opening IBI by a spring I85 having one end thereof fast to the dog and the other-end thereof fast, to the housing I 59. The spring I85 is also eflective to urge a lug I66 on the dog I64 toward notches as I61 formed in the periphery of the hub I68 on the gear I 59, which hub, as best snown in Fig. 11, projects into the housing I59, a collar I69 engaging anotherhub on the gear I58 to thereby hold the free end of the hub I68 in engagement with the housing I59 so as to thereby prevent axial movement of the As explained hereinabove, the clutch including the housing I59 is to be effective to stop the cylinder 22 at selected positions in order, for

. on the clutch dog I63 that is projected through theopening I6! in the housing I59, and normall the springs I19 and I199 are effective to dispose the nose portions of the stop pawls Hill;

and H00 in position to engage the nose I62.

However, one end of a. link I991) is connected through the intermediary of a pin and slot con-.

nection I690 to the pawl I'IIlb, while another link I69d is connected through the intermediary of a pin and slot connection I59e to the pawl I100,

- and the opposite ends of the links "59b and IBM;

are pivotally connected, as indicated at I997, to the free end of the arm llGa that extends from the shaft Illa. The links last and ma are so connected to the pawls "0b and 4100 through the intermediary of the pin and slot con nections I690 and IBSe that, when the rod. I2Ila is moved downwardly when the foot pedal I26, Fig. 1, is depressed, the noses of the pawls I101; and I are respectively retracted out of the path of travel of the nose I62. Therefore, when the foot pedal I26 is depressed and the pawls Ib and I100 are retracted, whichever one of these pawls has been engaging thenose I62 is withdrawn from engagement with this nose and thereupon the spring I65 is effective to so rock the dog I63 that the lug I66 thereon seats in one of the notches I61 in the hub I68. Preferably, a plurality of notches I61 are provided in the hub I68 so that when a stop pawl is retracted, as aforesaid, from engagement with the nose I62, the dog I63 will be quickly connected through the intermediary of the lug I66 with the hub I68 and therefore with the gear I58.

It will therefore be seen that when the foot pedal as I26 is depressed so as to free the nose I62 from engagement with a stop pawlas l10b or I100 to thereby enable the lug as I66 to seat in a notch as I61, the shaft I9a is connected with the gear I58 to rotate therewith. In this respect it is to be understood that the stop pawls I10b and I100 are mounted on the side frame member I50. in such related positions that when the nose I62 comes into engagement with one of these stop pawls the drum 22 will be quickly brought to rest in such position that access may be conveniently had to one or the other of the positions thereon whereat the end of a master sheet M is to be connected thereto. Thus once the foot pedal I26 has been depressed and the shaft I9a has been connected to the gear I58 and drums or cylinders as C and 22 are set in operation and the foot pedal is released, the springs I10 and I109 are effective to bring the stop pawls I10b and I100 into position to cooperate with the nose I62 and as soon as the nose I 62, for example, engages the stop pawl I10b, the dog I63 is so pivoted about the pivotal mounting I64 thereof against the effect of the spring I65 that the lug I66 is withdrawn from whatever notch I61 in which it has been seated and thereupon the drums C and 22 are at once brought to rest. Thus if the position of the pawl I10b has been related to the cylinder 22 so that the rocker 50 will be disposed in the position shown in Fig. 3 at the time" the nose I62 engages the pawl I10b, then the drum 22 will be brought to rest in such position that the end of a master sheet may expeditiously be connected to the rocker 50 in the manner described hereinabove. On the other hand, if the nose I62 engages the pawl I100, thenby reason of the relationship between the stop pawl I100 and the drum 22, the drum 22 will be brought to rest in such position as to dispose the bar 38 in position tohavethe end of a master sheet connected thereto. In any event, however, once the foot pedal I26 is released, the rotation of the drums C and 22 will be so arrested that the drum 22 will be brought to rest in such position as to enable one or the other of the ends of a master sheet to be connected thereto depending, of course, upon whether the stop pawl I10b or I100 has been engaged by the nose I62. Of course, if the drum 22 is brought to rest in the position shown in Fig. 3; for example, at a time when access is desired to the bar 48, then the foot pedal 26 is depressed only sufficiently to retract the stop pawls I101) and I100 and thereupon it is released so that when the nose I62 engages the stop pawl other than that with which it has been engaged the drum 22 will be brought to rest in the desired position.

In instances where resort is had to an arrangement such as that shown in Figs. 9, 10 and inders as C and 22 by grasping and rotating the hand wheel as I50, it will be necessary to effect" engagement of the clutch in order that the cylinders may be rotated for in such instances movement will be transmitted from the shaft a through the pinion I51 to the gear I56 and thence through the clutch including the housing I56 to the shaft I9a.

In many of the uses to which a printing machine embodying the present invention may be put it will be advantageous to in some instances print less than all of the image borne by the master sheet as M and while in certain instances this may be effected by masking the portion of the image that is not to be reproduced by applying a thin covering sheet over such portion of the image and, for example, adhesiyely securing this sheet to the master sheet, there will be instances where it will not be convenient to so mask the master sheet. Furthermore, in some instances that portion of the image that is to be eliminated in the course of making reproductions from the master sheet may be so arranged axially along the mastersheet when it is mounted on a drum as 22 that the sheets to receive the impressions may be so passed into the bite between the blanket and the platen roller that only the desired portion of the image along the axial extent thereof will be reproduced. This may be conveniently done by arranging a gauge to determine the position of the sheets relative to the blanket and therefore the master sheet so that only a portion of the image borne by the master sheet will be reproduced. In such instances an ofl'set will not be produced on the platen roller by reason of the spacing of the platen roller from the blanket in the manner explained hereinabove.

However, in other instances the portion of the image that it is desired to eliminate in at least selected of the impressions made onto sheet fed between the blanket and the platen roller may be surrounded by portions of the image which it is desired to reproduce, and when this occurs resort may be had, for example, either to an arrangement such as that shown in Figs. 12 to 15, inclusive, or that shown in Figs. 16 to 18, inclusive.

Referring first to Figs. 12 to 15, inclusive, the portions of the apparatus there illustrated which correspond to those described hereinabove are designated by corresponding reference characters except that in Figs. 12 to 15, inclusive, the suffix b is added to such reference characters. Moreover, the location of the portion of the image which it is desired to eliminate will be accurately ascertained particularly with respect to the position at which such portion of the image will appear when transferred to the blanket 20b, and in this respect, since the blanket and the master bearing the image are arranged for synchronic cooperation, it will be understood that an identical portion of the image is picked up by the blanket each time the blanket and master move into cooperating relation one with the other. Furthermore, since the portion of an image,

which it will be desired to cut off when resort is had to the arrangements shown in Figs. 12 to 15, inclusive, will usually be a portion that is surrounded by other portions of the image, we have, for the purpose of illustrating this aspect of our invention, shown an arrangement which will cause a portion of the image disposed substantially midway between the side edges of the master sheet and therefore the blanket as being the portion that is to be eliminated, and we have also shown this portion as being located in such position that it will appear on the face of the blanket 7 near one of the ends thereof and it will be understood that such an arrangement is merely illustrative of arrangements to which resort could be caresses 18 the portion of the image that is alisnod with this tangentially extending portion of the blanket isnot picked up by this portion of the blanket, wherefore, as it is called in the art, such portion of the image is cut off and will not therefore be transferred by the blanket 28b from the master I sheet Mb to a sheet fed into the bite between the cylinder Cb and the platen roller 2Ib.

It will be appreciated that a block as "I and the cooperating parts may -be located at any desired or required position relative to the periphery of the cylinder Cb so as to thereby enable radially slldable in the opening I19, the block "I being arranged so that it includes a face I12 that is formed to afford a continuation of the surface of the cylinder Cb. I

As best shown in Figs. 12 and 14, the inner'end tion of the blanket is drawn in of the block in is bifurcated to provide two branches I13 and I14 between which a shaft I15 is passed. the shaft I15 being journaled in the end walls I15 and I11 of the cylinder Cb. A pin I18 extends between the. branches I13 and I14 rearwardly of the shaft I15, and a spring I19 has one end thereof fastened to the pin I18 and the other end thereof is disposed about the shaft I9b. Thus the spring I19 is effective on the block I1I to tend to urge the surface I12 thereon away from As best shown in Figs. 12 and 14, the shaft I15 cooperating relation with the surface of the drum in the portion thereof disposed between the I branches I13 and I14 has two flattened portions I88 and IN thereon. The flattened portions I 88 and I8I formed on the shaft I15 are spaced from the center thereof in different amounts. Moreover, a plate I82, Figs. 13 and 15, is fast to the shaft I15 outwardly of the end wall I16 of the cylinder Cb, and a 'pin I83 projects from this plate andis disposed in position so that it may be conveniently grasped by the operator to thereby enable the shaft I15 to be rotated. Therefore, when the pin or handle I83 is grasped and the shaft I15 is rotated into a position which will dispose the surface I88 thereon in engagement with the bottom wall I84 of the bifurcation formed in the block I1 I, the effect of the spring I19 is so overcome that the surface I12 on the block IN is disposed to afford a continuation of the surface of the cylinder Cb and, when the blanket 28b is drawn taut over the surface of the cylinder Cb and the surface I12, the portion of the blanket aligned with the surface I12 is disposed m such position as to enable it to pick up a portion of the image carried by the master sheet Mb.

When, however, the pin I83 is grasped and the shaft I15 is rotated to present the surface .I8I to the wall I84, then under the influence of the spring I19 the surface I12 is retracted from 0ooperating relation with the periphery of the cylinder Cb, the surface I12 being shown in this position in Fig. 14. Thereupon, by reason of the fact that the blanket 29b is drawn taut on the periphery of the cylinder Cb and since the support afforded therefor by the surface I12 is withdrawn from cooperating relation therewith, the portion of the blanket 29b aligned with the surface I12, or, stated otherwise, aligned with the opening I19, assumes a tangential position relative to the periphery of the drum Cb to thereby be so retracted from the normal position thereof that this position of the blanket 29b is prevented from engaging the master sheet as Mb and therefore a cutoff to be effected upon retraction, of the' peripheral surface as I12 on a block'as I1I"in a desired or required position. However, in those instances where a rather substantial cutoff is to be effected, it has been follzid that if a per 0 such tangential relation, the edges defined at the ends of such tangentially extending portion sometimes cause a pickup of ink to be effected with the result of what is known as toning appears on the sheet receiving impressions-from the blanket. Hence, in those instances where the extent of the cutoil,-

peripherally of the blanket as 20b or acylinder as Cb, is of substantial length, we have found it advantageous to resort to the arrangement shown in Figs. 16, 17 and 18.

The form of the invention shown in Figs. 16, 17 and 18 embodies many parts which have been referred to hereinabove and where such parts appear in Figs. 16, 17 and 18 they are designated by a reference character such as that previously used to identify such a part, but in Figs. 16, 1'1 and 18 the suiiix 0 is added to each such reference character.

In the form of the invention shown in Figs. 16, 17 and 18 the extent of the block I1Ic is such that it is advantageous to form this block so that it will be substantially T-shaped in cross section, the block being bifurcated at the free the drum C0, and flattened portions I890 and I8Ic on a shaft I150 are effective in the manner explained hereinabove with reference to the portions I89 and I8I to dispose the surface I120 either in or out of cooperating relation with the periphery of the cylinder C0.

' In this instance, however, instead of causing the blanket 200 to assume a tangential position in the portion thereof aligned with the opening I upon retraction of the surface I from cooperating relation with theperiphery of the drum or cylinder C0, the portion 2000 of the blanket 290 aligned with the surface I120 is cut away from the remainder of the blanket 290 and is adhesively or otherwise suitably secured to the face I120. As best shown in Fig. 17, the opening that is thus formed in the blanket 290 is preferably enlarged so as to afford clearance about the portion of the blanket 280a that is secured to the surface I120 so that the portion 280a will not interfere with tightening of the blanket 200 on the periphery of the cylinder C0.

It will therefore be seen that when the surface I8I10 is engaged with the wall I880, the portion 20011 of the blanket is aligned with the the block I, the block Hi will be located at any desired or required position in the extent of the blanket as 200 so that a cutoff may b efi'ectecl at any desired position.

The arrangements shown in Figs. 12 to 18, inclusive, are such as to enable a retraction of a portion of the blanket or transfer mediun'nbut it will be understood that particularly in thbse instances where a relatively flexible master such as that to which Wescott Patent No. 2,134,165, patented October 25, 1938, pertains is utilized either the arrangement shown in Figs. 12 to 15 or that shown in Figs. 16 to 18 could be utilized. Thus if the arrangements shown inv Figs. 12 to 15 were incorporated in the cylinder as 2212, a master of the aforesaid character could be caused to assume the aforesaid tan ential or chordal relation with respect to the periphery of the cylinder 22b and just as in the case when the blanket b assumes a tangential or chordalrelation with respect to the periphery of the cylinderC, a cutoff would be efiected.

Likewise, if the arrangement shown in Figs. 16

shown in Figs. 12 to 18, inclusive, and equivalents thereof may be utilized to either effect retraction brake or resort may be had to a clutch arrangement'which will positively arrest movement of a drum or cylinderin selected or such positions. It will be appreciated that an arrangement of this character materially expedites the use of printing machines of the kind to which this invention pertains, particularly in those instances where but a relatively few impressions are to be made from each master sheet that is arranged in the machine.

Moreover, we have provided an arrangement which may be utilized to apply a treatment to a master sheet such, for example, as in the case of a lithographic master sheet as will render the non-image portions of the master sheet ink-repellent. The arrangement which we have provided is manually controlled and may therefore be rendered operative when and as required and furthermore, as explained hereinabove, the arrangement is such that the means for applying such a treatment to the master sheet may be rendered efiective either when the master sheet is initially installed in the machine or from time to time as impressions are being made from such a master sheet.

Furthermore, we have included in the printing machine an arrangement which will eflectively wipe ofl any excess from the master sheet of any fluid Or the like that may be applied thereto by to 18, inclusive, were incorporated, for example,

the manually-controlled means to which reference has just been made. Inasmuch as the means which efiects this wiping operation is so arranged in the machine that it may be expeditiously removed from or installed in the machine, such wiping means may at all timesbe kept in conditionjto perform its intended funcof a portion of a master or a portion of a transfer medium so as to thereby enable a cutoff to be effected. Moreover, in some instances it may be desirable to efiect more than one-cutofi and the portions which are thus desired to be cut on may be so related one to the other that there would be mechanical transfer in the event it was desired to incorporate the arrangements which would enable such cutoffs to be effected in a singlecylinder, and hence in such circumstances, or else-.

where as desired, an arrangement for enabling retraction of both a portion oi a master and a portion of the transfer medium may be incorporated in the respective cylinders on which such members are mounted. This would of course enable two portions of a master arranged in axial alignment along the periphery of the drum 22c, for example, to be cut off either singly or together and, of course, any other relation between the two portions to be cut ofi could be provided for by resorting to the inclusion of the means for effecting the cutoff in one or both of the two cylinders.

It will be appreciated from the foregoing descrlption that we have provided a printing machine in which portions of a drum. or cylinder to which ends of a master sheet are to be connected may be expeditiously brought to rest in. positions as will facilitate connection of the end of a master sheet thereto. As explained hereinabove, this desirable result may be accomplished either through the utilization of a friction clutch and vantageous.

tion.

Additionally, as explained hereinabove, the present invention also includes an arrangement which will enable a cutofi of selected portions of an image borne by a master sheet to be expeditiously efiected without resorting to masking the master sheet. Furthermore, this arrangement'is such that portions of an image surrounded by the image may be expeditiously cut oil which, it will be appreciated is cfttimes ad- Inasmuch as we have shown the means that enable such a cutoff as being efiected to be manually controlled, it will be understood that this means may be rendered inefiective or efiective as may be desired or required in the course of operation of the machine.

Thus while we have shown and described preferred embodiments of our invention, it is to be understood that these are capable of variation and modification and we therefore do not wish to be limited to the precise details set forth but desire to avail ourselves of such changes and alterations as fall within the purview of the following claims.

We claim:

1.. In a printing machine, a rotary drum embodying spaced apart means for attaching to the drum the respective ends of a master disposed onthe peri hery of the drum, driving means for said drum, clutch means interposed between said driving means and said drum, means for effecting engagement of said clutch means to set said drum in rotation, and means fo effecting disengagement of the clutch means and operative to bring about disengagement of said clutch means in such angular relation with the positions of the spaced apart means on said drum as to cause said drum to come to rest in selected positions 25 at which access may be readily had to the spaced 21 apart means for attaching a master to the drum to thereby facilitate attachment to the ends of a master to the drum.

2. In a printing machine, a rotary drum embodying spaced apart means for attaching to the drum the respective ends of a master disposed on the periphery of the drum, driving means for said drum, clutch means interposed between said driving means and said drum, means for effecting engagement of said clutch means to set said drum in rotation, and means fo effecting disengagement of the clutch means and operative to bring about disengagement of said clutch means in such angular relation with the respective positions of the spaced apart means on said drum as to cause said drum to come to rest in one or the other of two selected positions at one of which access may be readily had to one of said spaced apart means and at the other of which access may be readily had to the other of said spaced apart means to thereb facilitate attachment of the ends of a master to the drum.

3. In a printing machine, a rotary drum embodying spaced apart means for attaching to the drum the respective ends of a master disposed on the periphery of the drum, driving means for said drum, clutch means interposed between said driving means and said drum, means for effecting engagement of said clutch means to set said drum in rotation, and means in said clutch means effective to bring about disengagement thereof and to arrest movement of the drum in such angular relation with the respective positions of the spaced apart means on said drum as to cause said drum to come to rest in one or the other of two selected positions at one of which access may be readily had to one of said spaced apart means and at the other of which access may be readily had to the other of said spaced apart means to thereby facilitate attachment of the endsof a master to the drum.

4. In a printing machine, a rotary drum embodying spaced apart means for attaching to the drum the respective ends of a master disposed on the periphery of the drum, driving means for said drum, clutch means including a clutch member operative to set said drum in rotation, and means respectively disposed in predetermined angular relation with the spaced apart means on thereby facilitate attachment ofthe ends of a master to the drum.

WILLIAM R. ALLEN. CHARLES H. SAND.

REFERENCES CITED The following references are of record in the file of this patent:

Number Name Date 2,165,288 Mills July 11, 1939 1,213,203 Johnson 1 Jan. 23, 1917 2,106,732 Goldike Feb. 1, 1938 1,958,593 Schultze May 15, 1934 908,286 Lindman 1- Dec. 29, 1908 508,067 Turley Nov, 7, 1893 2,094,181 Morrison Sept. 28, 1937 470,797 Wheeler Mar. 15, 1892 2,012,350 Pym et a1. Aug. 27, 1935 901,964 Harris Oct. 2 7, 1908 1,124,620 Jerrain Jan. 12, 1915 2,083,043 Storck June 8, 1937 2,083,044 Storck 1 June 8, 1937 

